Vista-cpu running at 100 without running any program

Hi friends

I have strange problem with my PC now. Due to a recent crash, I'd to re-install my OS (Windows Vista Ultimate-Genuine).It was a clean installation. After the installation my CPU shows running @100% all the time. Then I reassembled the PC to apply thermal paste to the CPU.It didn't help.Checked with Bit Defender Internet security and other spyware tools.

The system configuration is :
Narmada TG-MK mainboard (G33/31+ICH9)-(re-configured HP dx 2450)
Q6600@2.4 Ghz Intel Quad CPU
Kingston DDR2@800FSB 4GB memory
500 SATA Seagate Baracuda HDD
Windows Vista Ultimate (genuine)/32bits

Here is the hijackthis log file :-


Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 16:33:39, on 13-09-2009
Platform: Windows Vista SP1 (WinNT 6.00.1905)
MSIE: Internet Explorer v7.00 (7.00.6001.18000)
Boot mode: Normal

Running processes:
C:\Windows\system32\taskeng.exe
C:\Windows\system32\Dwm.exe
C:\Windows\Explorer.EXE
C:\Program Files\BitDefender\BitDefender 2009\bdagent.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Program Files\uTorrent\uTorrent.exe
C:\Windows\system32\wbem\unsecapp.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Program Files\BitDefender\BitDefender 2009\seccenter.exe
C:\Program Files\Sunbelt Software\CounterSpy\SBAMTray.exe
C:\Program Files\Sunbelt Software\CounterSpy\SBAMUI.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Windows\system32\SearchFilterHost.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.microsoft.com/fwlink/?LinkId=69157
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O3 - Toolbar: BitDefender Toolbar - {381FFDE8-2394-4f90-B10D-FC6124A40F8C} - C:\Program Files\BitDefender\BitDefender 2009\IEToolbar.dll
O4 - HKLM\..\Run: [BDAgent] "C:\Program Files\BitDefender\BitDefender 2009\bdagent.exe"
O4 - HKLM\..\Run: [BitDefender Antiphishing Helper] "C:\Program Files\BitDefender\BitDefender 2009\IEShow.exe"
O4 - HKLM\..\Run: [SBAMTray] C:\Program Files\Sunbelt Software\CounterSpy\SBAMTray.exe
O4 - HKCU\..\Run: [Sidebar] C:\Program Files\Windows Sidebar\sidebar.exe /autoRun
O4 - HKCU\..\Run: [uTorrent] "C:\Program Files\uTorrent\uTorrent.exe"
O4 - HKUS\S-1-5-19\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'LOCAL SERVICE')
O4 - HKUS\S-1-5-19\..\Run: [WindowsWelcomeCenter] rundll32.exe oobefldr.dll,ShowWelcomeCenter (User 'LOCAL SERVICE')
O4 - HKUS\S-1-5-20\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'NETWORK SERVICE')
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search & Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O13 - Gopher Prefix:
O22 - SharedTaskScheduler: Windows DreamScene - {E31004D1-A431-41B8-826F-E902F9D95C81} - C:\Windows\System32\DreamScene.dll
O23 - Service: BitDefender Arrakis Server (Arrakis3) - BitDefender S.R.L. http://www.bitdefender.com - C:\Program Files\Common Files\BitDefender\BitDefender Arrakis Server\bin\Arrakis3.exe
O23 - Service: BitDefender Desktop Update Service (LIVESRV) - BitDefender SRL - C:\Program Files\Common Files\BitDefender\BitDefender Update Service\livesrv.exe
O23 - Service: CounterSpy Antispyware (SBAMSvc) - Sunbelt Software - C:\Program Files\Sunbelt Software\CounterSpy\SBAMSvc.exe
O23 - Service: SBSD Security Center Service (SBSDWSCService) - Safer Networking Ltd. - C:\Program Files\Spybot - Search & Destroy\SDWinSec.exe
O23 - Service: BitDefender Virus Shield (VSSERV) - BitDefender S. R. L. - C:\Program Files\BitDefender\BitDefender 2009\vsserv.exe

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End of file - 3995 bytes


Help me friends ! I invested all my savings to this PC.